diff --git a/stepmania/src/DateTime.cpp b/stepmania/src/DateTime.cpp
index b88b80aa6f..3f52e90e7b 100644
--- a/stepmania/src/DateTime.cpp
+++ b/stepmania/src/DateTime.cpp
@@ -196,6 +196,7 @@ static const char *MonthNames[] =
 };
 XToString( Month, NUM_Month );
 XToLocalizedString( Month );
+LuaXType( Month );
 
 RString LastWeekToString( int iLastWeekIndex )
 {
@@ -303,8 +304,8 @@ tm GetDayInYearAndYear( int iDayInYearIndex, int iYear )
 	return when;
 }
 
-LuaFunction( MonthToString, MonthToString( (Month)IArg(1) ) );
-LuaFunction( MonthToLocalizedString, MonthToLocalizedString( (Month)IArg(1) ) );
+LuaFunction( MonthToString, MonthToString( Enum::Check<Month>(L, 1) ) );
+LuaFunction( MonthToLocalizedString, MonthToLocalizedString( Enum::Check<Month>(L, 1) ) );
 LuaFunction( MonthOfYear, GetLocalTime().tm_mon );
 LuaFunction( DayOfMonth, GetLocalTime().tm_mday );
 LuaFunction( Hour, GetLocalTime().tm_hour );
diff --git a/stepmania/src/DateTime.h b/stepmania/src/DateTime.h
index 73bbb13532..60bb7c1824 100644
--- a/stepmania/src/DateTime.h
+++ b/stepmania/src/DateTime.h
@@ -1,6 +1,7 @@
 #ifndef DATE_TIME_H
 #define DATE_TIME_H
 
+#include "EnumHelper.h"
 #include <ctime>
 
 const int NUM_LAST_DAYS = 7;
@@ -21,6 +22,7 @@ const RString &MonthToString( Month month );
 const RString &MonthToLocalizedString( Month month );
 RString LastWeekToString( int iLastWeekIndex );
 RString LastWeekToLocalizedString( int iLastWeekIndex );
+LuaDeclareType( Month );
 
 tm AddDays( tm start, int iDaysToMove );
 tm GetYesterday( tm start );